Sanitary drain valve design

Abstract

A valve for sampling a process from a tank or conduit includes an internal cavity in communication with at least one inlet and an outlet. A valve actuating rod includes a sealing tip attached to one end thereof. The valve actuating rod is movable to open and close the inlet to the internal cavity. Furthermore, a seal is provided to isolate the valve actuating rod and the outside environment from the process. The seal is formed on the process side of the bottom wall of the internal cavity in order to ensure that the process material, cleaning material, steam, etc. drains completely out of the internal cavity of the valve.

What is claimed is:  
     
       1. A valve for draining a process from a tank or conduit, comprising: 
       a valve body;  
       a first inlet formed in said valve body;  
       an outlet formed in said valve body;  
       an internal cavity formed in said valve body and in communication with said first inlet and said outlet, said internal cavity being at least partly defined by a bottom wall having a first side facing the process and a second side facing away from the process;  
       a sealing tip, said sealing tip having a first side facing the process and a second side facing away from the process;  
       a valve operating rod, said valve operating rod being connected to said sealing tip and movable to move said sealing tip into sealing contact with an annular surface about said first inlet into said internal cavity to form a first seal for sealing the internal cavity from communication with the process;  
       a second seal, said second seal being a dynamic seal and being formed between said first side of said bottom wall of said internal cavity and said second side of said sealing tip to isolate said valve operating rod and the surrounding outside environment from the process.  
     
     
       2. The valve according to  claim 1 , wherein said bottom wall of said internal cavity includes a hole therethrough for receiving said valve operating rod, said bottom wall including a first portion around said hole being raised with respect to a second portion of said bottom wall immediately adjacent thereto, said first portion forming said first and second sides of said bottom wall and being sealed by said seal. 
     
     
       3. The valve according to  claim 2 , wherein said raised portion is a cylindrical portion having an outside diameter forming said first side of said bottom wall, and said sealing tip includes a sealing sleeve having an inside diameter for forming said second side of said sealing tip and for sliding on said outside diameter of said cylindrical portion, said second seal being located between said sealing sleeve and said cylindrical portion. 
     
     
       4. The valve according to  claim 1 , wherein a bottom most surface of said bottom wall has a continuously declining path toward said outlet to promote the drainage of the process out of said internal cavity.